Many electronic devices include one or more circuit boards comprising electronic components assembled on a circuit board panel. In order to manufacture high quality electronic devices in a cost effective manner, it is necessary to assemble the electronic components to the circuit board panel at a high speed and with great precision. These goals are achieved through automated assembly.
In an automated manufacturing environment, the circuit board is created by assembling the electronic components on an empty circuit board panel via an automated part placement machine. An example of such a machine is the model FCP-IV chip part placement machine manufactured and sold by Fuji Machine Manufacturing Company. The automated part placement machine receives the empty circuit board panel from a conveyor. A leveling apparatus of the part placement machine lifts the circuit board panel off of the conveyor and positions it for part placement. A placement head of the part placement machine places the electronic components or "parts" in predetermined locations on the circuit board panel. The leveling apparatus then places the assembled circuit board onto the conveyor.
To remain competitive in the industry, manufacturers must be able to manufacture different circuit boards via a single assembly line. This often requires that manufacturing equipment be capable of assembling circuit boards from panels having different thicknesses. Because of the high cost of the automated part placement machine, it is desirable that all the circuit boards be assembled using one automated part placement machine.
To accommodate circuit board panels having different thicknesses, the height of the leveling apparatus of the automated part placement machine must be manually adjusted or "hard tooled" to compensate for the different thicknesses of the circuit board panels. Currently, the procedure for adjusting the leveling apparatus has several undesirable characteristics. To make adjustments, the automated part placement machine is taken off line. This results in costly production down time. Additionally, adjusting the height of the leveling apparatus is a tedious and time consuming task that requires trial and error techniques to perfect each time an adjustment is made. Placement of parts on the circuit board following manual adjustments is often marked with a reduction in quality, including incidents in which circuit board panels become damaged due to mispositioning attributable to improper height adjustment. The height adjustment must be compensated repeatedly until such errors are eliminated.
Therefore, what is needed is a leveling apparatus that does not require manual height adjustment between sequential manufacturing runs of circuit board panels or substrates having different thicknesses.